CN107006082A

CN107006082A - RF heating system

Info

Publication number: CN107006082A
Application number: CN201580057323.7A
Authority: CN
Inventors: H·D·小吉姆瑞
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-10-23
Filing date: 2015-10-23
Publication date: 2017-08-01
Anticipated expiration: 2035-10-23
Also published as: ES2748703T3; US20190289684A1; CA2964468A1; AU2015335674A1; MX369761B; KR20170086031A; AU2015335674B2; AU2021201634A1; EP3210439A4; MX2017005133A; US11412586B2; EP3210439A1; US20220322504A1; WO2016065303A1; CA2964468C; US20160119984A1; CN107006082B; KR102374787B1; EP3554192B1; AU2021201634B2

Abstract

This disclosure relates to radio frequency (RF) heating system and method for quickly and uniformly heating multiple articles in conveyor line, the system includes being connected to the RF generators of RF waveguides, RF energy is sent to RF heating chambers by the RF waveguides, so that by RF energy conductions to the conveyer for being configured to make article transport through the RF heating chambers.

Description

RF heating system

The cross reference of related application

This application claims the priority of No. 62/067,976 U.S. Provisional Patent Application filed in 23 days October in 2014 Rights and interests, the entire disclosure of the application is herein incorporated by reference.

Technical field

The present invention relates generally to the system using radio frequency (300KHz-300MHz) energy warms article.

Background technology

Electromagnetic radiation is for by the mechanisms known of energy delivery to object.Electromagnetic radiation is penetrated in quickly and efficiently mode And it is favourable during many chemical industries that the ability of heating target is verified.In the past, radio frequency (RF) energy is Through to heat article for example, by sensing heating or dielectric heating.However, can be had using RF energy warms article Shortcoming.For example, the wavelength of RF energy, which may be such that, is difficult to effective means transmission and transmitting RF energy.The present invention relates to for Discovery that is minimized and/or eliminating and use the conventionally associated many shortcomings of RF energy warms article.

The content of the invention

Certain embodiments of the present invention provides a kind of radio frequency (RF) heating system, and it is heated with improved validity and efficiency Multiple articles.The heating provided by the RF heating systems can be used to carry out pasteurize or sterilization to article.The RF heating System can include following component：(a) RF generators, it is used to produce RF energy；(b) RF waveguides, it is configured to generally fill out Filled with liquid, and the RF energy produced by the RF generators can be transmitted when filled with the liquid；(c) RF heating chambers Room, it is configured to generally be filled with the liquid, and can be received by the RF waveguides when filled with the liquid The RF energy of transmission；And (d) transmission system, its be received in the RF heating chambers and be configured to the article just by The article is transported through into the RF heating chambers while RF energy warms.

Other embodiments of the invention provide a kind of method for being used to use radio frequency (RF) energy warms article.The RF adds Hot method can be comprised the steps of：(a) RF energy is made to pass through the generally RF waveguides filled with liquid；(b) RF energy is introduced Into the generally RF heating chambers filled with the liquid；And (c) transports through the RF using RF energy warms and heated The article of chamber.

Brief description of the drawings

Fig. 1 is the block diagram in exemplary steps/area of the RF heating systems of embodiments in accordance with the present invention configuration；

Fig. 2 is the section view isometric view of a part for the RF heating zones configured according to one embodiment of present invention, specific For illustrate how that RF energy is put on to the encapsulation for transporting through heating chamber using relative transmitter；

Fig. 3 is the end-view of Fig. 2 RF heating zones；

Fig. 4 shows the RF heating zones that RF energy is put on to article using unilateral transmitter；

Fig. 5 shows that the neighbouring unilateral transmitter of two on the same side using chamber puts on RF energy the RF of article Heating zone；

Fig. 6 shows that RF energy is put on article by the unilateral transmitter spaced apart of two on the opposite side using chamber RF heating zones；

Fig. 7 is the isometric view of the RF heating zones using relative transmission device, and the transmitter is oriented such that transmitter Most wide wall perpendicular to article direct of travel；

Fig. 8 is the side view of Fig. 7 RF heating zones；

Fig. 9 is the end-view of Fig. 8 RF heating zones；

Figure 10 is equipped with the section view isometric view of the RF heating zones of multiple dielectric field shaping devices；

Figure 11 is the cross-sectional view of Figure 10 RF heating zones；

Figure 12 is equipped with the exploded isometric view of the carrier of dielectric nest set system, and the system, which will be used for receiving, to be added in RF The article heated in hot-zone；And

Figure 13 is the cross-sectional view of Figure 12 carrier.

Embodiment

In many business processes, it may be necessary to heat a large amount of individual articles in quick and uniform mode.The present invention makes Article, or auxiliary heating article are quickly and uniformly heated with radio frequency (RF) energy.Can be in the RF heating systems of the present invention The example of the appropriate articles of heating can be including (but not limited to) food, medical fluid and medicine equipment.In one embodiment, originally The RF heating systems of text description can be used for the pasteurize or sterilization of the article heated.Generally, pasteurize be related to by One or more articles are rapidly heated to the minimum temperature between 70 DEG C and 100 DEG C, and sterilize and be related to one or more things Product are heated to 100 DEG C and 140 DEG C, 110 DEG C of minimum temperatures between 135 DEG C or 120 DEG C and 130 DEG C.

Fig. 1 is the overall pattern of the RF heating systems configured according to certain embodiments of the present invention.As shown in fig. 1, one Or multiple articles can be initially charged into pre-add hot-zone 10, wherein article can be pre-heated to substantial uniform pre-heating temperature (for example, 20 DEG C to 70 DEG C).Once through preheating, just article can be incorporated into RF heating zones 12.In RF heating zones, it can make The RF energy at least a portion of heating zone 12 is discharged into one or more RF transmitters by being described in more below Quickly heat article.Heated article is then optionally by holding area 14, wherein article can be maintained at into steady temperature Up to specified time quantum.Then, article can be then delivered to cooling area 16, wherein can be quickly reduced to the temperature of article properly Disposal temperature (for example, 20 DEG C to 70 DEG C).

Fig. 1 RF heating systems can be configured to many different types of articles of heating.In one embodiment, in RF plus The article heated in hot systems may include food, for example water fruits and vegetables, meat, wheaten food, prefabricated meal and even beverage.At it In its embodiment, the article heated in RF heating systems may include the medical fluid or medical treatment and/or dental appliance of encapsulation. The article handled in RF heating systems can have any suitable size and shape.In one embodiment, each article can With at least about 2 inches, at least about 4 inches, at least about 6 inches and/or no more than about 18 inches, no more than about 12 inches or not Greater than about 10 inches of length (longest dimension)；At least about 1 inch, at least about 2 inches, at least about 4 inches and/or be not greater than about 12 inches, no more than about 10 inches or no more than about 8 inches of width (the second longest dimension)；And/or at least about 0.5 inch, At least about 1 inch, at least about 2 inches and/or no more than about 8 inches, no more than about 6 inches or no more than about 4 inches of depth (shortest dimension).Article may include end item or encapsulation with general rectangular or prismatic shape, or may include to lead to Cross institute's interlocking item of RF heating systems or the continuous net of encapsulation.The project or encapsulation can be by including plastics, cellulose Any material construction of material and other generally materials transparent to RF, and RF can be passed through via one or more transmission systems Heating system, is discussed in detail below the embodiment of the transmission system.

According to one embodiment of present invention, each of above-mentioned preheating, RF heating, holding and/or cooling area can To be defined in single vessel, and in another embodiment, at least one of above-mentioned level can be in one or more independent devices Defined in ware.According to one embodiment, at least one of above-mentioned steps can be filled with the device of fluid media (medium) at least part Carried out in ware, wherein the article handled can be immersed in the fluid media (medium) at least in part.The fluid media (medium) can be with It is the gas or liquid of the dielectric constant of the dielectric constant with more than air, and can is with class in one embodiment It is similar to the liquid medium of the dielectric constant of the dielectric constant of article handled.This liquid medium can have at 20 DEG C at least 40th, 60 or 70 and/or no more than 120,100 or 90 dielectric constant.Water (or liquid medium including water) can be especially suitable for In the system to heat edible and/or medical treatment device or article.In one embodiment, if it is desired, so in processing The additive such as oil, alcohols, glycols and salt optionally can be added to liquid medium to change or strengthen its thing by period Rationality matter (for example, boiling point).

RF heating systems can include at least one transmission system, for article to be conveyed into one passed through in above-mentioned treatment region Or it is multiple.The example of suitable transmission system can be transmitted including (but not limited to) plastics or rubber belt conveyer, chain conveyer, roller Device, flexibility or flexure conveyer, gauze conveyer, bucket type conveyer, tube conveyer, screw spreader, slot type or vibration more Conveyer, and combinations thereof.The transmission system can include any number of indivedual transmission lines, and can arrange in any way as suitable In in process vessel.The transmission system that RF heating systems are utilized can be configured in the generally fixed position in vessel, or At least a portion of system can be adjusted in the lateral or vertical direction.

In RF heating zones 12, article can be rapidly heated by the heating source using RF energy.As used herein, art Language " RF energy " refers to the electromagnetic energy with the frequency more than 300KHz and less than 300MHz.In one embodiment, RF adds The various configurations of hot-zone are using the RF energy with 50 frequencies for arriving 150MHz.Except RF energy, RF heating zones can also be optional Ground utilizes one or more of the other thermal source, for example conduction or Convective Heating or other conventional heating methods or device.However, In RF heating zones 12 to the energy that heats article at least about 25%, about 50%, about 70%, about 85%, at least about 90%, extremely Few about 95% or generally can be all the RF energy from RF energy sources.In certain embodiments, used in RF heating zones With heat article energy be less than 50%, less than 25%, less than 10%, less than 5% or generally without energy be by tool The electromagnetic radiation for having the frequency more than 300MHz is provided.

According to one embodiment, RF heating zones 12 can be configured to the temperature of article being increased above minimum threshold temperature Degree.In wherein RF systems are configured to make one embodiment of multiple sterilisation of objects, the minimum threshold temperature (and RF adds The operation temperature of hot-zone 12) can at least about 120 DEG C, at least about 121 DEG C, at least about 122 DEG C and/or no more than about 130 DEG C, no Greater than about 128 DEG C, or no more than about 126 DEG C.RF heating zones 12 can be operated under approximate ambient pressure, or it can include one Or multiple pressurization RF chambers, the chamber is at least about 5psig, at least about 10psig, at least about 15psig and/or is not greater than about 80psig, no more than about 60psig are operated no more than about under 40psig pressure.In one embodiment, pressurization RF chambers can To be the chamber filled with liquid with operating pressure so that the article heated can reach higher than the liquid wherein used The temperature of the normal boiling point of medium.

Required temperature can be heated in the relative short time cycle by the article of RF heating zones 12, this is in some cases The damage of article can be made or degrade minimum.In one embodiment, can have at least about 5 by the article of RF heating zones 12 Second, at least about 20 seconds, at least about 60 seconds and/or no more than about 10 minutes, be not greater than about 8 minutes or no more than about 5 minutes flat Equal residence time.In identical or other embodiments, RF heating zones 12 can be configured at least about 15 DEG C/min (DEG C/ Min), at least about 25 DEG C/min, at least about 35 DEG C/min and/or no more than about 75 DEG C/min, no more than about 50 DEG C/min Or under no more than about 40 DEG C/min of the rate of heat addition, at least about 20 DEG C of the mean temperature increase for the article for making to heat, at least About 30 DEG C, at least about 40 DEG C, at least about 50 DEG C, at least about 75 DEG C and/or no more than about 150 DEG C, no more than about 125 DEG C or little In about 100 DEG C.

Fig. 2 and 3 provides the isometric view and side view of one embodiment of RF heating zones 20, wherein RF energy productions respectively In RF energy generators 22, transmitted via coaxial conductor 24 from RF generators 22, waveguide is coaxially arrived using upper and lower part Cross portion 28a, b to be sent in waveguide 26a, b that upper and lower part is filled with water, transport through waveguide 26a, the b filled with water, pass through Cross optional inductive iris 32a, b and into transmitter 34a, b that upper and lower part is filled with water, send out upper and lower part The RF heating chambers 36 that transmitter 34a, the b and entrance filled with water is filled with water.In RF heating chambers 36, in article 38 When (for example, food encapsulation) is moved along in the transmission system that can include carrier 40 and chain driver 42, described in RF energy warms Article.Although a pair of transmitters 34a, b that Fig. 2 is only shown with, it should be appreciated that can be used two pairs or more to hair spaced apart Emitter.

Coaxial conductor 24 includes external conductor and inner conductor.Such as possible illustrated best in Fig. 3, external conductor terminates at ripple Lead at 26 wall, and center conductor extends through a wall of waveguide 26, into the inside of waveguide 26, and reaches (or passing through) ripple Lead 26 opposite wall.Dielectric sleeve surrounds center conductor, and wherein center conductor penetrates the wall of waveguide 26.This dielectric sleeve serves as barrier Wall is to prevent liquid to be delivered to from the inside of waveguide 26 in coaxial conductor 24.The dielectric sleeve can easily with waveguide 26 Seal and generally the material of microwave is made.In one embodiment, the dielectric sleeve can be filled by glass fibre Polytetrafluoroethylene (PTFE) (PTFE) material is formed.

It has been found that filling waveguide 26, transmitter by using the liquid with than air closer to the dielectric constant of water 34 and RF heating chambers 36, RF energy can be transferred to more effectively and efficiently the article 38 heated.Fill waveguide 26, transmitting The liquid of device 34 and RF heating chambers 36 serves as transmission medium, and RF energy to waveguide transition portion 28a, b from being coaxially directed to thing The transmission medium is transported through during product.Fill waveguide 26, transmitter 34 and RF heating chambers 36 liquid can it is preprocessed with Minimize its electrical conductivity.The electrical conductivity of the liquid (for example, water) be preferably smaller than 100mS/m, less than 50mS/m, be less than 10mS/m, less than 5mS/m or less than 0.5mS/m.In certain embodiments, distilled water or deionized water can be used to fill waveguide 26th, transmitter 34 and RF heating chambers 36.

Waveguide 26, transmitter 34 and RF heating chambers 36 can be to opening, so as to permit waveguide 26, transmitter 34 and RF each other The liquid contained in heating chamber 36 is shared each other.However, waveguide 26, transmitter 34 and RF heating chambers are the portions of sealing system Point, the sealing system does not allow liquid leakage to go out RF heating zones, but RF heating systems can be included for recycling and/or changing The system of liquid in RF heating zones.

Waveguide 26, transmitter 34 and RF heating chambers 36 can contain a small amount of air.However, waveguide 26, transmitter 34 and RF Generally all internal volumes of heating chamber 36 will preferably have liquid, such as water.Therefore, waveguide 26, transmitter 34 and RF At least 75,90,95,99 or 100% of the internal volume of heating chamber 36 can be filled with liquid.

Waveguide 26, transmitter 34 and RF heating chambers 36 allow the size of these components to compare ripple filled with the liquid such as water Lead the situation of 26, transmitter 34 and RF heating chambers 36 filled with air much smaller.For example, the waveguide for carrying RF energy can With general rectangular cross section, wherein the size of most wide wave guide wall is at 5 to 40 inches, 10 to 30 inches or 12 to 20 inches In scope, and most narrow wave guide wall size in 2 to 20 inches, 4 to 12 inches or 6 to 10 inches of scope.

The deep infiltration that can be provided energy in the article 38 just handled using RF energy warms article 38, can make required transmitting The number of device 34 is minimum, and can provide high field uniformity for more uniform heating.

Fig. 4 illustrates the replacement RF heating zones 40 using unilateral transmitter 42.Fig. 5 is illustrated to be adopted on the same side of chamber With unilateral neighbouring transmitter 50a, b replacement RF heating zones 50.Fig. 6 is illustrated has what one side was spaced apart on the opposite side of chamber Transmitter 62a, b replacement RF heating zones 60.

Fig. 7,8 and 9 provide isometric view, side view and the end-view of RF heating zones 70, wherein RF waveguides 74 most respectively The propagation axis of article of the most wide wall 76 of wide wall 72 and RF transmitters 78 in transmission system.RF waveguides have been shown And/or this orientation of RF transmitters enhances field uniformity.

Figure 10 and 11 illustrates optional dielectric field shaping device 80a, b, c, d, e, f, g, h, and it is to strengthen RF heating chambers Field uniformity in room is to prevent the big thermograde in heating thing boiling product.The dielectric field shaping device can be by absorbing few RF Energy and material with the different dielectric constants of water from filling RF heating chambers is formed.For example, the dielectric field modeling The dielectric constant of shape device is smaller than 20, less than 10, less than 5, or less than 2.5.

Figure 12 and 13 shows carrier 90, and it keeps grid 94a, b and dielectric comprising external frame 92, upper and lower part Nest 96.Dielectric nest 96 includes the multiple openings for being used for receiving the individual articles 98 heated.Dielectric nest 96 is generally filled individual Space between other article 94.The dielectric that the dielectric constant of dielectric nest 96 is preferably substantially similar to the article 98 heated is normal Number.For example, the dielectric constant of dielectric nest 96 can in the 50% of the dielectric constant of the article 98 heated, in 25%, In 10% or in 5%.In certain embodiments, dielectric nest 98 have at 20 DEG C at least 2,10,20,40 or 60 and/or less In 160,120,100 or 90 dielectric constant.

The RF heating systems of the present invention can be that the business level heating system of large numbers of items can be handled in relative short time. RF heating systems as described herein can be configured to realize at least about 2 encapsulation per minute of every transmission line, every every point of transmission line At least 15 encapsulation of clock, at least about 20 encapsulation per minute, at least about 75 encapsulation per minute per transmission line per transmission line, or often The overall productivity of transmission line at least about 100 encapsulation per minute.

As used herein, term " encapsulation per minute " refer to according to following procedure can be handled by RF heating systems with breast The total number of gel-filled 8 ounces of MRE (fast food) encapsulation of albumin：From Ameriqual Group LLC (indiana ,USs State Evans Wei Er cities) commercially available 8 ounces of MRE encapsulation filled with lactalbumin gel pudding is connected to and is positioned at edge in pudding Multiple hygrosensors at five equidistant positions at each of x, y and z axes line interval, the axis is derived from the envelope The geometric center of dress.Then the encapsulation is positioned in the RF heating systems assessed, and heated until in detector Each record is higher than the temperature for specifying minimum temperature (for example, for 120 DEG C of decontamination system).Needed for realizing this Temperature Distribution Time and on heating system physics and dimension information can then to calculate by it is per minute encapsulation in terms of overall manufacturing Rate.

Invention described above preferred form would act only as explanation, and should not be used for interpreting in restrictive, sense The scope of the present invention.Without departing from the spirit of the invention, those skilled in the art can be easily made to old above The obvious modification for the exemplary embodiment stated.

Inventor states that it wishes to depend on doctrine of equivalents hereby, on not departing from substantially as in appended claims The literal scope of the invention of statement but any equipment outside the scope, it is reasonable just with the assessment present invention to determine Scope.

Claims

1. a kind of radio frequency (RF) heating system for being used to heat multiple articles, the RF heating systems include：

RF generators, it is used to produce RF energy；

RF waveguides, it is configured to generally be filled with liquid, and can transmit and produced by the RF when filled with the liquid The RF energy that raw device is produced；

RF heating chambers, it is configured to generally be filled with the liquid, and can receive logical when filled with the liquid Cross the RF energy of the RF waveguide transmissions；And

Transmission system, it is received in the RF heating chambers and is configured to while the article is just by RF energy warms The article is transported through into the RF heating chambers.

2. RF heating systems according to claim 1, it further comprises for transmitting what is produced by the RF generators At least one coaxial pipe of RF energy.

3. RF heating systems according to claim 2, it further comprises being received in the RF waveguides and being coupled to institute That states coaxial pipe coaxially arrives waveguide transition portion, wherein described be coaxially configured to receive from described coaxial to waveguide transition portion The RF energy of conduit and RF energy is transferred in the waveguide.

4. RF heating systems according to claim 1, it further comprises RF transmitters, and it, which is used to receive, comes from the RF The RF energy of waveguide and RF energy is transferred in the RF heating chambers.

5. RF heating systems according to claim 4, wherein the most wide wall of the RF transmitters be essentially perpendicular to it is described Article is oriented by the direction of propagation of the RF heating chambers.

6. RF heating systems according to claim 1, it further comprises one be received in the RF heating chambers Or multiple dielectric field shaping devices.

7. RF heating systems according to claim 6, wherein the dielectric constant of the dielectric field shaping device is less than 20.

8. RF heating systems according to claim 1, wherein the transmission system includes Jie for being used to receive the article Electric nest.

9. RF heating systems according to claim 8, wherein the dielectric nest is with the dielectric constant in the article Dielectric constant in 25%.

10. RF heating systems according to claim 1, it further comprises the preheating in RF heating zones upstream Area.

11. RF heating systems according to claim 10, it further comprises the cooling zone in RF heating zones downstream.

12. RF heating systems according to claim 11, it further comprises being located at the RF heating zones and the cooling Holding area between area.

13. one kind is used to include using the method for the multiple articles of radio frequency (RF) energy warms, methods described：

(a) RF energy is made to pass through the generally RF waveguides filled with liquid；

(b) RF energy is incorporated into the generally RF heating chambers filled with the liquid；And

(c) article of the RF heating chambers is transported through using RF energy warms.

14. method according to claim 13, wherein the liquid in the waveguide and the RF heating chambers is water.

15. method according to claim 13, wherein the liquid in the waveguide and the RF heating chambers has Electrical conductivity less than 50mS/m.

16. method according to claim 13, it further comprises RF energy supplies to the RF via coaxial conductor Waveguide.

17. method according to claim 16, it, which further comprises using, is received in the RF waveguides and is coupled to institute The coaxial of coaxial conductor is stated RF energy is transferred in the RF waveguides to waveguide transition portion.

18. method according to claim 13, it further comprises launching via the RF for being generally filled with the liquid RF energy from the RF waveguides is transferred to the RF heating chambers by device.

19. method according to claim 18, wherein the most wide wall of the RF transmitters is essentially perpendicular to the article Oriented by the direction of propagation of the RF heating chambers.

20. method according to claim 13, wherein RF energy are fed to the RF heating chambers by relative RF transmitters Room.